Method and system for controlling cavity height of a leaky wave antenna for RFID communications

• US 8,618,937 B2
• Filed: 06/09/2010
• Issued: 12/31/2013
• Est. Priority Date: 06/09/2009
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Rofougaran, Ahmadreza, Rofougaran, Maryam
• Primary Examiner(s): La, Anh V
• Application Number:
  US12/796,841
• Publication Number:
  US 20100308997A1
• Time in Patent Office: 1,301 Days
• Field of Search: 3405721-5729, 340/10.1, 340/10.34, 340/10.4, 340/693.1, 340/693.5, 343/700.MS, 343/702, 343/767, 343/768, 343/770, 343/772, 343/776, 343/777, 343/795, 343/860, 343/873, 343/895, 307/10.1, 235/492, 235/488, 235375-385
• US Class Current: 340/572.7
• CPC Class Codes: G01S 13/06 Systems determining position data of a target
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01Q 1/2283 mounted in or on the surface of a semiconductor substrate as a chip-type antenna or integrated with other components into an IC package
• CPC Class Codes: H01Q 13/20 Non-resonant leaky-waveguide or transmission-line antennas; Equivalent structures causing radiation along the transmission path of a guided wave
• CPC Class Codes: H01Q 13/22 Longitudinal slot in boundary wall of waveguide or transmission line H01Q13/203 takes precedence
• CPC Class Codes: H01Q 15/006 Selective devices having photonic band gap materials or materials of which the material properties are frequency dependent, e.g. perforated substrates, high-impedance surfaces
• CPC Class Codes: H01Q 15/0066 said selective devices being reconfigurable, tunable or controllable, e.g. using switches
• CPC Class Codes: H01Q 15/23 Combinations of reflecting surfaces with refracting or diffracting devices
• CPC Class Codes: H01Q 19/06 using refracting or diffracting devices, e.g. lens radome H01Q1/42
• CPC Class Codes: H04B 1/0458 Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 7/24 for communication between two or more posts wireless communication networks H04W

Abstract

Methods and systems for controlling cavity height of a leaky wave antenna for RFID communications are disclosed. In this regard, an RFID transponder may receive RF signals via a leaky wave antenna and modulate a frequency of a backscattered signal by controlling a height of a resonant cavity of the leaky wave antenna. The height of the resonant cavity may be controlled via a micro-electromechanical system. The RFID transponder may modulate an amplitude of the backscattered signal by controlling an input impedance of the RFID transponder. The input impedance may be controlled by switching a load in and out of a receive path of the RFID transponder. The input impedance of the RFID transponder may be controlled by switching between a plurality of feed points of the leaky wave antenna. Each of the plurality of feed points may be located in a different position in the resonant cavity of the leaky wave antenna.

Claims

1. A method for communication, the method comprising:

receiving RF signals via a leaky wave antenna within a radio frequency identification (RFID) transponder; and

modulating a frequency of a backscattered signal associated with said received RF signals by controlling spacing between surfaces of said leaky wave antenna.

2. The method according to claim 1, comprising controlling said spacing between surfaces of said leaky wave antenna via a micro-electromechanical system (MEMS) switch.

3. The method according to claim 1, comprising controlling said spacing between surfaces of said leaky wave antenna via one or more switches.

4. The method according to claim 1, wherein said leaky wave antenna is integrated within and/or on a packaged integrated circuit.

5. The method according to claim 1, comprising modulating an amplitude of said backscattered signal by controlling an input impedance of said RFID transponder.

6. The method according to claim 5, comprising controlling said input impedance by switching a load in and out of a receive path of said RFID transponder.

7. The method according to claim 5, comprising controlling said input impedance by switching between a plurality of feed points of said leaky wave antenna.

8. The method according to claim 1, wherein said received RF signal causes charge to accumulate on one or more capacitors in said RFID transponder resulting in a voltage that is utilized to control and/or power one or more portions of said RFID transponder.

9. The method according to claim 8, comprising controlling, utilizing said voltage, a switch that connects and disconnects a battery of said RFID transponder to one or more other components of said RFID transponder.

10. The method according to claim 8, comprising powering, utilizing said voltage, a radio subsystem and/or a processing subsystem of said RFID transponder.

11. A system for communication, the system comprising:

one or more circuits for use in an RFID transponder comprising a leaky wave antenna, said one or more circuits being operable to;

receive a RF signal via said leaky wave antenna; and

modulate a frequency of a backscattered signal by controlling a height of a resonant cavity of said leaky wave antenna.

12. The system according to claim 11, wherein said RFID transponder comprises a micro-electromechanical system (MEMS) switch and said height of said resonant cavity is controlled via said micro-electromechanical system.

13. The system according to claim 11, wherein said leaky wave antenna is integrated within and/or on an integrated circuit package.

14. The system according to claim 11, wherein said leaky wave antenna is integrated within and/or on an integrated circuit.

15. The system according to claim 11, wherein said one or more circuits are operable to modulate an amplitude of said backscattered signal by controlling an input impedance of said RFID transponder.

16. The system according to claim 15, wherein said one or more circuits are operable to control said input impedance by switching a load in and out of a receive path of said RFID transponder.

17. The system according to claim 15, wherein said one or more circuits are operable to control said input impedance by switching between a plurality of feed points of said leaky wave antenna.

18. The system according to claim 11, wherein:

said one or more circuits comprise one or more capacitors and diodes;

said received RF signal causes charge to accumulate on said one or more capacitors resulting in a voltage that is utilized to control and/or power at least a portion of said one or more circuits.

19. The system according to claim 18, wherein:

said one or more circuits comprise a switch that connects and disconnects a battery of said RFID transponder to one or more other components of said RFID transponder; and

said switch is controlled utilizing said voltage.

20. The system according to claim 18, wherein said one or more circuits comprise a radio subsystem and a baseband processing subsystem and said voltage is utilized to power said radio subsystem and/or said processing subsystem.